Wheeled vehicle



Feb, Z5, i193@ J. c. MOCK WHEELED VEHICLE @www Filed Nov. 9, 1932 4 Sheets-Sheet l INVENTOR james 6 Moek Feb., Z5, i936., 1. c. MOCK WHEELED VEHICLE Filed NOV. 9, 1952 4 Sheets-Sheet 2 Feb. 25, E936., J, C. MOCK ll@ WHEELED VEHI CLE Filed NOV. 9, 1932 4 Sheets-Sheet 5 INVENTOR jamas @L mwen www@ 25, Egg@ C. MOCK Z@ WHEELED VEHICLE Filed` NOV. 9, 1932 4 Sheets-Sheet 4 $55 lill!! i1 HHIHHH Il II IHHIIIHIIIIIII HI i INVENTOR hm@ @Si web ATTO NEY Patented Fels. 25, 1936 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to wheeled vehicles and railway rolling stock, and more particularly to an improved car truck construction convertible for operation either on or off the rails, so that a car equipped with one or more of the improved trucks may be used not only for rail travel in the conventional manner, but as well in running over highways or the ground.

An important object of the 4invention is the provision of such a convertible truck incorporating separate wheels for rail and highway travel in which novel means is provided for raising the wheels not in use clear of the ground or rails, or other supporting surface, and for preventing any of such wheels from being raised until all are first in engagement with the supporting surface.

A further object is the provision of novel wheel raising and lowering mechanism so designed that it is never necessary to lift the weight of the vehicle in operating the Same, which requires very little power to operate, and which may be motivated manually by one or more motors.

Another object of this invention is the provision of improved locking means to prevent raising or lowering of either the rail or highway wheels unless the brakes of the vehicle are set, and for locking the raised and lowered wheels in their respective positions, in whichever relative positioning they may be.

Still another object is the provision of means to prevent lowering of the highway wheels into operative position unless the truck and car are aligned and parallel, and for holding them rigidly in that relation as long as the road wheels are lowered and the rail wheels elevated.

A still further object is the provision of improved electrical controlling means for regulating the raising and lowering of the wheels, for preventing raising both sets of wheels at once, etc.

Still further objects will readily occur to those skilled in the art upon reference to the following description and the accompanying drawings in which Figure l is a View partly in section and partly in side elevation of a truck incorporating the principles of this invention, the same being illustrated attached to a railway car which is fragmentarily shown.

Figure 1a is a fragmentary and more or less diagrammatic side view of part of the truck chassis with the outer spring frame, wheels, etc. removed, bringing out the locking means (Cl. 10S- 215) for preventing simultaneous raising of both rail and highway wheels.

Figure 2 is a fragmentary side view of a railhighway car incorporating the principles of this invention, showing the same adjusted for highway use and adapted to be attached to a motor tractor or the like, (unshown) by means of which the car may be hauled when off the rails.

Figure 3 is a composite view the left half of which is primarily in end elevation although 10 partly broken away, and the right half of which is a vertical section taken substantially on the line 3 3 of Figure 1 and looking in the direction of the arrows.

Figure 4 is a detail view partly in end elevation, the line 4 4 of Figure l rection of the arrows.

Figure 5 is a detail side view taken substantially on the line 5-5 of Figure 4 and looking in the direction of the arrows.

Figure 6 is a schematic diagram showing the wiring of a preferred arrangement of the electrical controlling and operating apparatus employed in conjunction with the invention, and

Figure 7 is a diagrammatic top plan View of the controller.

Referring now to the drawings, reference character IU designates the body of a car or other wheeled vehicle, which may be in the nature of a railway box car, although its construction and precise nature are unimportant, as my invention primarily concerns itself with mechanism and the control and operation thereof. No attempt has accordingly been made to illustrate or describe the car in detail. The car is preferably of lighter construction than an ordinary railway box car, however, and lighter alloys of aluminum and the like may be used to still further reduce the weight if desired. The car I ll is shown in Figure 2 as equipped at either end with one of my improved trucks, both trucks being shown adjusted for highway or other travel oif the rails. The trucks incorporate separate wheels as l2 and I3 for rail and highway travel respec- 45 tively, the former ordinarily anged and the latter rubber tired, as shown, and so arranged that either the rail or highway wheels may be lowered into engagement with the supporting surface and the others lifted clear thereof. When the road wheels I3 alone contact the ground, car l0 may be hauled by a tractor (not shown) after the fashion of an ordinary truck trailer, or in any other desired manner, while of course when the rail wheels are lowered and the partly in section and 1r taken substantially on and looking in the dihighway wheels raised the car may be used for Yrail travel.

Each Lconvertible truck may, as shown, incorporate a sprung frame I pivotally secured to the car body as at I3, having side portions I5', bolted to and extending downwardly therefrom, and a cross bracing member, shown in the form of a plate I1 extending across the legs of the channel or U-sectioned sprung frame member so formed. The -bottom plate I1 is here shown secured to the sprung frame by means of nuts and bolts. These, as well as the nuts and bolts securing together the other portions as I5-I5' of the sprung frame, are designated I8. Shackled to the sprung frame I5 as at I9 are semi-elliptic springs 28, to the centers of which are attached Ysecuring members 2| which support through the master shafts 22a, 22h, and. 22c,.the unsprung frame assembly, generally designated 23, which is arranged within the sprung frame. mental compression springs as 24 may be arranged between the outer ends of the front and back semielliptic springs Vand the frame I5. The upper ends of the supplemental springs en'- gage asuitably'formed inwardly projecting su lporting portion .|52 of the sprung frame, while the lower end of each compression spring is secured to the Yend of its spring 2D by means of a rod 25 extending upwardly through the spring 24 and an aperture 23 in the memberV I52 into pivotal'engagement with the shackle member 21 `carried by the endof the spring 2|).V The rod carries at itslower end a cap 28 in which the compression spring is seated, and adjustment may be provided by the securing and locking nuts 29 which hold the cap in place.

`Half bearings for the shafts 22a, 22h and 22e Y are formed in the unsprung frame 23, and are completed by bearing caps 30 as bolted to the frame. As shown in Figure 1, one of the master shafts is arranged above'each pair ofY wheels. The wheels are mounted upon axle shafts as l2-I3, and the axles, and so the wheels are adapted to be raisedand lowered by means of pitmen 3l, the lower ends of which are loosely 'secured to ,the axles immediately inside the wheels while their upper ends engage eccentrics 32 carried by the ends of the master shafts. The eccentrics are of such throw that in a half revolution they raise and lower the wheels I2-V-I3 a desired distance, l

'Meana for turning the master shafts, and so the ec'centrics may be carried by the inner or un- Asprung frame 23. In the construction shown the master shafts. are arranged to be driven by electric motors 33 coupled through spur gears 3d and mitre gears 35 to worms 36, each of which drives a worm wheel 31, one of which Vis Vfast on Veach of Athe master shafts. One such gear train motorsr33 and this intermediate reducing gearing through which they drive the master shafts'are all supported by and journalled in the unsprung frame 23. Electrical means which willpresently be described in detail are provided for controlling the operation of the motors 33, Vand such electrical control may of course be so'arranged that all wheels must be lowered before they can be raised, and that only one set of wheels: can be raised at one time, thereby preventing the necessity of lifting the car and its load in operating any of the wheels up or down. Switches for assisting in controlling the motor circuits may be mounted in the frame 23 adjacent the axle shafts and arranged to be thrown as the axles Y Supple- V approach fully raised and fully lowered positions. The details of construction of such switches are of course unimportant. The casing housing one of the same is shown at 91 in Figure 3. YI n order to provide for raising and lowering the wheels by hand, the motor shafts may be squared, as at 98 for reception of a crank or wrench (not shown).

Mechanical means may also be provided for locking the axles I2-I3 andfso the wheels in position, to prevent raising or lowering of anyY of the wheels while the vehicle is in motion as well as to take the vertical load off the pitmen 3l. Such means may comprise a series of locking plates 38, one for each of the axles.V The locking Vplates are slotted as at 39-440 for engagement about the axles, and are secured together as by bars 4I to move as-a unit.V The double bent or substantially Z-shaped slots 39 within which the rail wheel axles I2 arearranged will be seen to be alike in shape and disposition, while the reverse or generallyS'shaped slots 4B within which the road wheel axle i3 travels are so oppo- Y sitely disposed that the horizontal portions of the slots may lockV the road wheels in raised position and the rail wheels in lowered position when the locking plates are slid in a commonl direction, and vice versa, but cannot lock both at once either in raised or lowered position. When the locking plates are in the centralV position in which they areV shown in Figure l, the axles may travel vertically in Vthe vertical portions of the slots. It will be seen that thewheels might be locked in the positions in which they are shown by moving the locking'plates. to the left.

The locking plates are further connected at their upper extremities by bars 42, and in thel upper portion of each plate is another slot 43 so that the plates may travelvfreely longitudinally of the truck without interfering with the master shafts 22a, 22h, and 22e. The slidable locking plate assembly will be seen to be hung from the unsprung portions of the truck, one on each side thereof arranged between thev inner or unsprung frame4 23 and the side plates I5 of the outer or sprung frame. Eachlocking plate assembly is slidable by'means of a connecting rod 44 pivotally attached at one extremity to the locking plate assembly and at the other to a crank pin 45 which may be carried by a gear 46 mounted on shaft 41 which is carried by a hanger 48 secured to the unsprung frame 23. Gear 46 mayy be turned to slide the locking plates by means of a pivotal baffle or guard plate 54 may be arranged to swing between the aperture 53 and the squared shaft 50, as shown in Figure 4. The baffle 54 is so connected that when the brake rod A55 is moved to set the brakes of the vehicle, the baffle is moved clear of the aperture 53, while when the rod is moved'to release the brakes the baille is moved to block the aperture 53 and prevent insertion of the crank. The rod 55 is of course connected to the usual or any desired brake rigging (not shown) with which the vehicle maybe provided.

Fast on the shaft 58 is arranged a disc 56, in the periphery Aof which is a slot 51, so arranged As best shown in Figures 4 that when uppermost it lies opposite another slot 58 in the rod 55 when that rod is in brakeset position. Vertically reciprocable between the slots is a dog 59 having an upper end adapted to t in the slot 58 and a lower end adapted to lit in the slot 51, and of such length that there is not room for the dog between the disc and the rod unless one or the other of the slots is in alignment with the dog, and so connected to the vane 54, as by means of the dog-carrying lever 60, link 6|, and the lever arm 62 attached to the vane, that when the portion 59 is out of the slot 51, and the arm 60 so raised, the vane is swung to the non-interfering position in which it is shown in Figure 5; to which non-interfering position in which it will be seen to be swingable, however, only when the slot 58 is in alignment with the dog, which occurs, as above stated, only when the rod 55 is in the position it occupies when the brakes are set. The lever arm 6|] is pivoted on a xed pin 63.

Thus with the mechanism in the position shown in Figures 1 and 5, the rod 55 being in the brake-set position and the vane 54 swung clear of the squared shaft, manipulation of the crank 5| in a manner to turn the crank pin 45 a quarter turn counterclockwise will result in moving the locking plates tothe left to secure the axles in their shown position, and would also put the slot 51 in uppermost position and in alignment with the bottom of the dog 59, which would then drop into the slot. The vane 54 will then fall to a position in which it covers the crank hole 53 as soon as the crank is removed, and the brake rod 55 is freely movable under normal operation of the brakes, being then no longer held in set position, but it will be seen that save when the rod is in brake-set position the dog cannot be moved upwardly to release the vane and the crank shaft and so permit manipulation of the sliding locking plates. When in such position however, the arm 50 may be lifted to swing the vane clear of the crank hole, as by means of a key (not shown) which may be inserted in the casing 52 through the keyhole 64 for engagement therewith.

It is of course necessary, when the rail wheels are lowered and the device arranged for rail haulage that the truck be free to swivel with respect to the car, whereas when the road wheels are lowered and the rail wheels raised to enable using the device as a trailer, at least one truck must be locked against swiveling with respect to the body. This result may be obtained by means of the locking pin 65, which is slidable in a cylindrical supporting boss 66, carried by the unsprung frame 23. The upper end of the rod may be projected into the socket 61 fastened to the under side of the car body only when the truck and body are parallel. The rod 65 projects downwardly through the frame 23, carrying at its lower extremity a cam follower in the form of a roller |68. The rod is adapted to be raised and lowered by the cam |69, mounted on the Shaft 41 which also carries the gear 55 locking plate actuating crank 45. The cam is so contoured that when the shaft 41 is turned to move the locking plates to the locked position they occupy when the rail wheels are lowered and the road wheels raised, the rod 65 is lowered clear of socket 61, and the truck is accordingly free to swivel, while when the shaft 41 is turned to move the locking plates to any other position, the rod 65 is forced upwardly into the socket 61 and locks the truck in longitudinal alignment with the car body. It will be obvious that the plunger cannot be forced into the socket, and accordingly the locking plates cannot be moved from the position in which they hold the rail wheels down and the road wheels up, unless the truck and body are in alignment, thus preventing use of the road wheels with the truck loose. The electrical circuit through the motor used for actuating the road wheels is arranged to be broken when the plunger is out of the socket 61, the contacts 68-59 being arranged in that circuit and constituting a safety switch adapted to be completed by the plunger 65, the contact 68 being arranged in the socket 61 and the contact 69 being mounted on the supporting boss 6E and slidably contacting the rod 65. This switching arrangement further prevents accidental lowering of the road wheels while the truck is free to swivel in a manner which will presently be more particularly described in connection with the electrical controlling system. To further lock the axles |2-|3' in position in the horizontal portions of the slots 39-40 in the locking plates, there may be provided vertically slidable locking members 10, generally of inverted U-shape, adapted to be vertically reciprocated by cam slots 1| and followers 93 carried by the locking members and engaging therein. The cam slots are formed in a horizontally slidable bar 12 carried by the unsprung frame 23 and having formed upon its end adjacent the locking plate actuating mechanism just described a rack 13, meshing with the gear 46 in such manner that upon turning the gear a quarter turn in either direction from the position in which it is shown in Figure l (that is, to lock the rail and highway wheels in either relative positioning) the locking members 15 are free to drop into the downturned ends of the slots 1 I, until they project into the slots 39--40 between the axles and the vertical portions of such slots, thus holding the axles in the ends of the horizontal portions of these slots.

As shown in Figure 1 the slide plate members I5 of the sprung frame are arranged to form vertical slots as 14 in which the axles |2-|3' may slide when being raised or lowered by the pitmen 3|, while at the upper ends of each such slot the frame members are cut away to allow swinging of the pitmen while following their eccentrics.

Also fast on each of the master shafts 22a, 22h and 22C is preferably arranged a disc as 99a, 99h, 99e, peripherally kerfed or slotted as at Illa, |051), |500. The discs are concentric and the slots have tapering sides and are similarly posi- I tioned therein, as shown in Fig. a. Between the two discs BSc-99h is arranged a slidable locking bar |ll| having ends tapered to t in the slots and of such length that it is free to move only when the slots are in opposed aligned relation; while it holds the shaft carrying the disc in whose slot it is engaged immovable until the slots are so aligned, preventing movement of both shafts at once. Thus with the rail wheels lowered and road wheels raised, as shown in Fig. la, it is impossible to change the positioning of the master shaft 22a to raise the rail wheels until master shaft 22h has been turned a half revolution to lower the highway wheels, at which time the slot |0019 is aligned with the locking bar IGI, after which shaft 22a may be turned to raise the rail wheels, movement of disc 99a forcing the locking bar to the left and its farther end into slot |691) under the cam action of the sloping sides of slot `Illc upon upon the tapered end of the bar. It

Yerally designated 1li.

will beV seen that thereafter shaft 22h cannot be turned to raise the road wheels until the Vrail wheels have been lowered. by turning the shaft 22d and disc to again put the slot |090, inthe shown position, pernntting turning of the disc |832) and movement of the locking bar to the right. There is thus provided a positive mechanical lock preventing simultaneously upward retraction of the wheels, and assuring that at least one pair shaii always be lowered to support the weight of the car. Simultaneous lockingof the other paircf rail wheels maybe provided by the auxiiiary locking bar lilic, connected to the locking bar ii Afor movement as Va unit therewith, as by the connecting bar ili, and engageable with a slot |880 in disc 99e only when bar |9| is engaged in slot mila.'

VFor controlling the three direct current motors by means of which the rail and highway wheels and axles are ordinarily raised and lowered there is preferably provided some suchcontrolling arrangement as is schematically Yshown in Figure 6, in which 33 and 333 represent the commutators of the motors used toV raise and lower the rail wheels, and 332 the commutator of the motor used to raise and lower the road wheels; reference characters |33', |332, and |333 correspondingly representing the eld of each. A source of direct current is indicated by the battery 75, between which and the several motors contacts are ladapted to be completed by a controller gen- The several axles |2-|3 are also diagramatioally shown inY this gure together with the contact carrier members `|'|-'|8-'|9 of the switches, 8|, 82, 83 respectively, which'are' actuated in response to raising and lowering of the axles, Each contact carrier carries three contacts (generally undesignated but clearly shown in Fig. 6) adapted to close the appurtenant pairs of adjacentl contacts Vwhen in either raised or lowered position. No attempt has been made to show the mechanical features of construction of the switches, which might obviously takev any of various well known They are arranged to be thrown, however, by ver-Y tical movements of the axles, Vas by means of yokes il', '18', 13 connected to the contact car'V riers and having spaced arms engageable by the axies as they near` the ends of their vertical travel.

The switches may be enclosed in casings as 91 mounted adjacent the axles in general as indicated in Figure 3.

When the handle 80 of the controller, shown in plan in Fig. 7, is moved to the position desighated A in that view, it closes contacts A and A" to lower the 'highway wheels. Since these wheels are initially raised however, (as indicated in Figure 6 by the positioning or" the axle |3) the circuit through contacts A from the negative battery terminal is broken at switch 82 by Y the raising of the contact carrier i8 and deadending of the lead connected to conductor 88. The circuit through the motor eld |332 is completed Yfrom the positive terminal of the battery 15 through contacts A', wire 88,and reversing switch 82, the current passing from the field |332 to the commutatoi` 332 through the central contact of contact carrier 18, and being completed back to the negative battery terminal through wire 85,Y the end contacts 86-81 of contact carriers 'I1-19 (switches 3|-83, which are closed by reason of the .lowered positioning of the axles |2') and through the contacts 68-89 to the battery. When the axle I3 reaches the lowered position, but not until then, the contact carrier in the same manner in which switch 82 controls the road wheel motor. A description of the manner in which one of these switches functions in controlling the raising of one of' wheels will accordingly suiilce to indicate the manner of controlling not only both pairs of railwheels, but the highway wheels as well. Considering the circuit-of switch 8|, shown on the right in Figure 6, the parts of and connected to which willY be seen to be like and arranged similarly to those comprising and controlled by switch 83, it will be seen that the eld of the motor is designated |33', and the commutator 33. Closing the contacts B-B" energizes the eld and commutator` portions of the rail wheel motors, the elds and so Vthe motors, being reversed, however, to

raise the wheels. The currentr hows from the positive battery'terminal through contacts B and wires 89 to the left hand contact 90 ofcontact carrier 1? whence it flows Ydirectly through the field |33', then the middle switch contact, commutator 33 and back Vto the negative' battery terminal through wire 9|, contacts 92 of switch Y 82, which contacts are then closed, and safety contacts 68-69. This raises the rail wheels and throws the contact carriers Vl-i9 back'tothe dotted raised positions, breaking the cir-cuit by dead-ending the positive line 89 at contar-.ts 90.

In lowering the rail wheels the contr-aller isY moved to a position C in which it closes contacts C-C", reversely energizingthe same motors controlled by switches 8|-83 through wires 92--92, Vin the same manner described in connection with lowering the road wheels under the control of switch 82. It will be apparent that during this operation the contact carrieres VV-19 are raised, contact carrier '|152 lowered. passes from the positive terminal of thebattery through contacts C' and lines 92-972 to the left hand switch contacts, reversing switch, elds |33', |332, central contact arm switch contacts, commutators 33332 and back to the 4negative battery terminal through wire 9|, contact 92 of switch 82, and contactsV 685-69.

In moving the road wheels up, the operationV tive terminal of the battery through wire 88 Vto switch contact 902, whenceV it Yows directly through the field |332 without passing through the reversing switch, central switch Contact, commutator 332, and back to the negative battery terminal through switch contacts 86 and 81 of switches 8 |'-83, and safety switch 68--69. `When the axle travel is completed andthe switch The current 2,032,219 thrown, the line 88 from the positive battery terminal is dead-ended at Contact 962.

It is believed that the operation of the construction will be apparent from the foregoing description, but it might briefly be summarized as follows: When the car reaches the end of a rail run, the wheels being in the positions in which they are shown in Figure 3, with the locking plate assembly in the left rather than the central position, however, and the locking bars 'il lowered to hold the axles in the ends of the horizontal portions of slots 39-40, the baie 54 guarding crank-hole 53, and locking pin clear of socket 5l by reason of the least-diametered portion of the heart-shaped cam GQ being uppermost, and it is desired to shift the wheels, the brakes are rst set, thereby aligning slots 53 (Fig. 5) with the dog 55. The key is then inserted in keyhole i, and the lever 60 lifted, thereby swinging `r the vane 54 free of the crank hole 53. The crank is then inserted and turned until the locking plate assembly is in the central position shown, with the vertical portions of the slots in alignment with the axles. In so adjusting the truck which is to be at the rear in the road haulage, this also forces pin 65 into socket 61, thus closing the circuit to the road wheel elevating motor at this point and locking the truck against swiveling, whereas in so adjusting the truck which is to be at the front in the road haulage the pin 65 may be removed and the switch contacts 68-69 shorted, or the plunger 65 otherwise rendered inoperative, so that the car may be hauled over the road by means of a draw bar or other suitable draft rigging attached to the truck thus left free to swivel. With either truck under consideration, however, the controller handle BEI is next turned to position A, lowering the road wheels, and then to position B to raise the rail wheels, after which the crank handle is turned to turn the crank 45 another quarter turn in the same direction, moving the locking plate assembly to the extreme right hand position and so locking the rail wheels in the up and the road wheels in the down position. At this time the auxiliary locking members l@ again fall, the followers dropping into the depressed portions at the other ends of the slots il, and slot 51 is again aligned with the dog 59, allowing the dog to fall into the slot and the vane 5d to cover the crank hole as soon as the crank is removed, after which, by means of a tractor or the like, the car may be hauled to its desired destination oif the rails.

The hauling arrangement is of course optional and might be varied to suit the convenience or conditions of service, for example both trucks might be locked against swiveling and the road wheels arranged upon steering knuckles after the fashion of the usual motor car and truck front axie construction and steered in any desired way, either by a separate operator and steering gear or by connection to the drawbar. So also but one of the convertible trucks might be used and a non-convertible rail truck of more conventional construction used for rail travel, while for road travel the end of the car so borne might be lifted from the rail truck and swivelly attached to the rear end of a tractor adapted also to support the same, which likewise is a common method of haulage well known in the art and requiring no further elaboration.

When it is desired to again place the car on the rails, the convertible truck or trucks are reversely adjusted; the baiie 54 of each is swung out of the way when the brakes are set in like manner, and the crank handle is applied and turned to rotate crank pin i5 a quarter turn in the opposite direction, again releasing the locking plates by moving them to the central position shown. The controller is moved to position C to lower the rail wheels, and then to position D to raise the road wheels. The crank handle is turned to complete a half revolution of the crank pin, sliding the locking plate assembly all the way to the left, to lock the rail wheels down and the road wheels up, also allowing pin 65, if the truck was locked thereby against swiveling, to fall from socket 6'! by again turning the least-diametered portion of cam G9 uppermost, and aligning plate 54 with dog 59, so that the crank hole guard plate 54 falls over the slot as soon as the crank handle is removed. As soon as both trucks are so adjusted, or the other end of the car is again placed on a truck suited for rail travel, if only one convertible truck is used, and the car placed on the rails, the car is again in condition for railway use.

Now having described the invention and the preferred embodiments thereof, it is to be understood that said invention is to be limited, not to the specic details herein set forth, but only by the scope of the claims which follow:

What I claim is:

1. A wheeled vehicle convertible for travel on or on" rails, comprising a body, a truck supporting the same, a plurality of axles carried by the truck, a pair of flanged wheels carried by one of said axles, a pair of unflanged wheels carried by another, means for independently raising and lowering each of said axles and the wheels carried thereby, and journaling and supporting means for suspending the vehicle from either pair of axles when lowered.

2. A convertible truck for supporting a wheeled Vehicle for travel on or olf rails, comprising flanged and unflanged wheels and axles independently connecting wheels of each type, an unsprung frame, vertically movable members supported by the unsprung frame and carrying the axles, means also carried by the unsprung frame for moving said members to raise and lower the axles, a sprung frame, and guide members for insuring vertical movement of the axles carried by the sprung frame.

3. A convertible truck for supporting a wheeled vehicle for travel on or oi rails, comprising anged and unflanged wheels, axles independently connecting wheels of each type, an unsprung frame, vertically movable members supported by the unsprung frame and carrying the axles, means also carried by the unsprung frame for moving said members to raise and lower the axles, slidable locking members also carried by the unsprung frame for securing the axles in raised or lowered position, a sprung frame, and guide members for insuring vertical movement of the axles carried by the sprung frame.

4. In a wheeled vehicle convertible for travel on or oif rails, a body, a truck supporting the same and normally free to swivel relatively thereto about a substantially vertical axis, locking means for securing the truck and body against such relative swiveling and in aligned relation, a plurality of axles carried by the truck, flanged wheels carried by one of said axles, unflanged wheels carried by another, means for independently raising and lowering each of the axles and the wheels carried thereby, and means for preventing lowering of the uniianged wheels when said truck locking means is in unlocked position.

5. In a wheeled vehicle convertible for travel on or off rails, a body, a truckv supporting the same and normally free to swivel relatively thereto about a substantially Vertical axis, locking Y means for securing the truck and body against of said wheel and axle assemblies independently,

and circuit-breaking means incorporated with Y said locking means for preventing energization of the lowering means for the unflanged wheels when said locking means is unlocked.

6. In a wheeled vehicleconvertible for travel on or off rails, a body, a truck supporting the same and normally free to swivel relatively thereto about a substantially vertical axis, locking means for securing the truck and body against such relative swiveling and in aligned relation, a plurality of axles carried by the truck, anged Wheelsrcarried by one of said axles, unr'langed wheels carried by another, a slidable lockingk member for' simultaneously securing one of the axles Vin raised and thev other in lowered position and vice versa, common actuating means for said locking means, arranged Vto release said truck locking means when said axle locking means secures the axle carrying the flanged wheels in lowered and the axle carrying the unflanged wheels Y in raised position.

7. In a wheeled vehicle convertible for travel on or off rails and incorporating brake rigging,

a body, a truck supporting the same, a plurality of axles carried thereby, flanged wheels carried by one of said axles, unflanged wheels carried by another, means for independently raising and lowering each of said wheel and axle assemblies, means for locking said wheel and axle assemblies against raising and lowering movement and for securing the wheels of one type in raised While IUSV the'others are in lowered position, and vice Versa,

and guard means for preventing actuation of said locking means when the brake rigging is in brake released position.

JAMES C. MOCK. 

